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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>Hi folks-</span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>&nbsp; In the course of trying to integrate a custom interactor
with a render window inside a vtkTkRenderWidget, I discovered a couple of
strange things that I was hoping someone could explain:</span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>&nbsp;</span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>1) You can&#8217;t (or so it seems) assign a render window
that&#8217;s inside a vtkTkRenderWidget to a vtkRenderWindowInteractor. Upon
execution, it pops up a barrage of empty &#8220;Application Error&#8221; windows
and then apparently deletes them back to front in the same order it created
them, leaving the most recently created one. In the console window there are a
bunch of errors like this:</span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>&nbsp;</span></font></p>

<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>bgerror failed to handle background
error.</span></font></p>

<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>&nbsp;&nbsp;&nbsp; Original error:
Object named: mainRWI, could not find requested method: EnterEvent</span></font></p>

<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>or the method was called with
incorrect arguments.</span></font></p>

<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>&nbsp;</span></font></p>

<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>&nbsp;&nbsp;&nbsp; Error in bgerror:
can't make &quot;.bgerrorDialog&quot; its own master</span></font></p>

<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>bgerror failed to handle background
error.</span></font></p>

<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>&nbsp;&nbsp;&nbsp; Original error:
Object named: mainRWI, could not find requested method: MouseMoveEvent</span></font></p>

<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>or the method was called with
incorrect arguments.</span></font></p>

<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>&nbsp;</span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>Why do these errors occur? Why does the interactor not like
render windows that have been placed inside TkRenderWidgets?</span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>&nbsp;</span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>2) Noting that I can nevertheless interact in a TkRenderWidget,
I figured there was an interactor there somewhere and checked for a GetInteractor
method on the render window to see if it has one, and to my happy surprise, it
does. (I guess the interactor&lt;-&gt;window relationship is bidirectional &#8211;
cool.) However, when I do &#8220;renWin GetInteractor&#8221;, instead of seeing
a familiar and comforting &#8220;vtkTemp1&#8221; (for varying values of &#8216;1&#8217;
</span></font><font size=2 face=Wingdings><span style='font-size:11.0pt;
font-family:Wingdings'>J</span></font><font size=2 face=Arial><span
style='font-size:11.0pt;font-family:Arial'>), I see &#8220;duh_renWin_iren&#8221;.
What gives? Is there a hack in the TCL wrapper generator code that returns
creative names if the method being wrapped is vtkRenderWindow::GetInteractor()?
And is this indicative of something going on here that I need to be concerned
with when manipulating the returned interactor object?</span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>&nbsp;</span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>Thanks,</span></font></p>

<p style='margin:0in;margin-bottom:.0001pt'><strong><b><font size=6
face="Monotype Corsiva"><span style='font-size:24.0pt;font-family:"Monotype Corsiva";
font-weight:normal'>Chris</span></font></b></strong></p>

<p><font size=2 face="Times New Roman"><span style='font-size:10.0pt'>--<br>
Christopher R. Volpe,
Ph.D.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>
Senior
Scientist&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Email: <a href="mailto:cvolpe@ara.com">cvolpe@ara.com</a><br>
Applied Research Associates,
Inc.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Voice: </span></font><font
  size=2><span style='font-size:10.0pt'>919-582-3380<br>
  </span></font><font size=2><span style='font-size:10.0pt'>8540 Colonnade
    Center Dr., Ste 301</span></font><font size=2><span style='font-size:10.0pt'>&nbsp;
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Fax: 919-878-3672<br>
</span></font><font size=2><span style='font-size:10.0pt'>Raleigh</span></font><font
 size=2><span style='font-size:10.0pt'>, </span></font><font size=2><span
  style='font-size:10.0pt'>NC</span></font><font size=2><span style='font-size:
 10.0pt'> </span></font><font size=2><span style='font-size:10.0pt'>27615</span></font><font
size=2><span style='font-size:10.0pt'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Web: <a href="http://www.ara.com/">www.ara.com</a></span></font></p>

<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>&nbsp;</span></font></p>

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